The present invention relates to atmospheric probes and relates in particular to probes for detecting the occurrence and the build-up of ice to avoid personal injury, loss of life and property loss or damage.
Such probes are useful to monitor the occurrence of and the build-up of ice upon aircraft, surface craft, power lines and aerial structures in general.
Typical prior art devices for indicating the accretion of ice, are disclosed and described in a series of U.S. Pat. Nos. 3,996,787, 4,053,127 and 4,095,456, issued on Dec. 14, 1976, Oct. 11, 1977 and June 20, 1978, respectively to Geoffrey Edgington and assigned to Lucas Industries, Ltd. The Edgington patents deal with a gas system where ice accretion causes (1) orifice restriction, (2) diaphram deflection, or (3) a pressure differential in the system.
A further disclosure appears in U.S. Pat. No. 4,553,137, issued Nov. 12, 1985 to Marxer et al. in which the change in frequency of a vibrating element is related to the build-up of ice.
These inventions appear to be limited to aircraft applications and involve vibratory or rotating elements or other movable members exposed directly to the these prior art devices are prone to generate confusing signals in snow, slush, sleet and rain.